The present invention relates generally to milking of animals in milking spaces on a movable floor. More particularly, the invention relates to a method and apparatus for the milking of animals on the moving floor involving automatic adjustment of the speed of the moveable floor on the basis of an estimated milking time of the animals on the moving floor and attached to milking units.
Movable parlours are used for milking animals, such as cows, in order to reduce the milking time in comparison to static parlours. The movable parlours are generally equipped with an automatic animal entrance and exit, which provide for an efficient movement of the animals to and from the stalls. Sensors at the entrance and the exit register, for instance by means of transponders on the animals, which animals that enter respective leave the platform. This registration enables automatic determination of the individual animals that are present on the platform at any time.
There are different types of movable parlours. The most common type has a platform, which revolves around its own axis so as to perform a rotary motion. The platform thus has an over all circular form However, other types of movable parlours may have a linear, or partly linear, mode of operation and consequently have a non-circular form, e.g. a conveyor belt. Both of these main types of movable parlours can be subdivided into classes on basis of how milking spaces are arranged on the parlour. In the case of rotary parlours, the animals may face either outwards or inwards on the platform. The present invention is applicable to all of the movable parlours mentioned above.
The international patent application WO97/37530 describes a construction having an implement with a movable floor on which cows are milked in milk boxes by one or more milking robots. The speed of the movable floor is adjusted on basis of either the estimated milking time of the cows on the movable floor or the estimated residence time on the movable floor. The estimated milking time is in turn determined from an historical average milking time of the animals in question or from an estimated longest milking time of an animal presently on the movable floor. Correspondingly, the estimated residence time is in turn determined from either an historical average residence time of the particular animals or from an estimated longest residence time of those particular animals. Alternatively, these values can be derived from real time measurements of the cows during actual extraction of milk.
This known automatic adjustment of the speed of the movable floor is intended to increase the occupancy rate of the implement in comparison to manually operated floors and as a result thereof also improve the throughput, i.e. the retrieved amount of milk per time unit.
However, due to the varying speed of the movable floor it is difficult to bring animals through the entrance gate, onto the movable floor and attach them to milking units at a rate, which matches the speed variations. This is particularly the case when an operator manually attaches milking units to the animals.